Semi-automatic document handler

ABSTRACT

Faster document handling for a xerographic copier is disclosed with automatic ejection of documents from the copying platen into a document output tray by sheet drive wheels at one edge of the platen, and automatic platen cover lifting, both controlled by a logic and timing circuit. The platen cover is spaced slightly above the platen for low friction document removal but maintains copying focus. A pivotable document input tray partially flexurally separates the documents. A magnetic platen cover latch is manually unlatchable merely by lifting the platen cover, or automatically unlatched electrically through the logic and timing circuit after a document is ejected, by a simple cam arrangement.



1. In a copying apparatus with a document copying platen and an overlayable platen cover holding documents against the platen for copying, the improvement comprising: platen cover latching means for retaining said platen cover over said platen for the copying of documents on said platen, said latching means comprising a permanent magnetic latch between said platen cover and said copying apparatus which can be manually unlatched merely by manual lifting of said platen cover, said latching means including automatic unlatching means for automatically unlatching said platen cover subsequently to the completion of said copying of documents on said platen, said copying apparatus further including automatic platen cover lifting means for automatically lifting said platen cover away from said platen when said latching means is unlatched, and wherein said automatic unlatching means comprises electrically driven mechanical camming means forcibly camming said platen cover away from said copying apparatus sufficiently to slightly separate and unlatch said permanent magnetic latch so that said automatic platen cover lifting means lifts said platen cover away from said platen subsequent to the completion of said copying of documents on said platen.
 2. The copying apparatus of claim 1 wherein said latching means is at least one permanent magnet in said platen cover and a magnetically attractable material area on said copying apparatus adjacent said platen and magnetically engaged by said permanent magnet when said platen cover is pulled against said platen.
 3. The copying apparatus of claim 1, wherein said camming means is a rotatable cam in said platen cover, and wherein said electrical unlatching means comprises electrical solenoid means in said platen cover substantially spaced from said camming means for reducing the inertia of said platen cover operatively connected to said camming means by elongate connecting means to rotate said camming means against said copying apparatus.
 4. In a copying apparatus with a document copying platen and an overlayable platen cover for holding documents against the platen for copying, the improvement comprising: platen cover latching means for retaining said platen cover over said platen for the copying of documents on said platen, said latching means comprising a permanent magnetic latch between said platen cover and said copying apparatus which can be manually unlatched merely by manual lifTing of said platen cover, said latching means including automatic unlatching means for automatically unlatching said platen cover subsequently to the completion of said copying of documents on said platen, said copying apparatus further including automatic platen cover lifting means for automatically lifting said platen cover away from said platen when said latching means is unlatched; said copying apparatus further including ejection means for rapidly automatically ejecting documents from said platen, wherein said ejection means comprises document engaging sheet drive means in said platen cover selectively automatically actuatable in response to the completion of copying of documents on said platen, said sheet drive means being driven for a predetermined time period sufficient to eject documents from said platen; and wherein said automatic unlatching means including electrical logic and timing means and being electrically operated by an electrical signal from said logic and timing means, said logic and timing means providing said electrical signal upon the completion of a predetermined time period count running from the completion of copying of a document on said platen during which time period count said sheet drive means is being driven.
 5. The copying apparatus of claim 4 wherein said automatic unlatching means comprises an electrically actuated camming means forcibly camming said platen cover away from said copying apparatus sufficiently to slightly separate and unlatch said permanent magnetic latch.
 6. The copying apparatus of claim 5 further including manual switch means on said platen cover operatively connecting with said copying apparatus and said logic and timing means to initiate copying of a document on said platen and to also control the actuation of said ejection means and said automatic unlatching means, in that order, by said logic and timing means.
 7. In a copying apparatus with a document copying platen and an overlayable platen cover for holding documents against the platen for copying, the improvement comprising: platen cover latching means for retaining said platen cover over said platen for the copying of documents on said platen, said latching means comprising a permanent magnetic latch between said platen cover and said copying apparatus which can be manually unlatched merely by manual lifting of said platen cover, said latching means including automatic unlatching means for automatically unlatching said platen cover subsequently to the completion of said copying of documents on said platen, said copying apparatus further including automatic platen cover lifting means for automatically lifting said platen cover away from said platen when said latching means is unlatched; wherein said automatic unlatching means comprises an electrically actuated camming means forcibly camming said platen cover away from said copying apparatus sufficiently to slightly separate and unlatch said permanent magnetic latch; and wherein said automatic platen cover lifting means comprises spring means connecting to said platen cover and having sufficient spring force to lift and hold said platen cover substantially away from said platen upon the unlatching of said platen cover latching means either manually or by said automatic unlatching means; and wherein said camming means is a rotatable cam in said platen cover spaced from said spring means, and wherein said electrical unlatching means comprises electrical solenoid means in said platen cover substantially spaced from said camming means for reducing the inertia of said platen cover, operatively connected to said camming means by elongate connecting means to rotate said camming means against said copying apparatus. 